Visayan wrinkled hornbill  (Aceros waldeni)

The Visayan wrinkled hornbill gains its common name from the prominent and wrinkled bony crest, known as a casque, which is situated on the top of the bill (2). This medium-sized bird has predominantly black plumage, glossed with a green sheen, although there is a large white band on the centre of the tail (4). The male has a striking reddish head, neck and upper breast and a red bill topped by a particularly large 'casque' (4). The facial skin is a bright saffron-yellow (2).

Endemic to the Western Visayan Islands of the central Philippines and historically known from Panay, Guimaras and Negros of that group (5). The wrinkled hornbill is today reduced to remnant populations on Panay and Negros and the total wild population may be as low as 50 mature individuals (5).

Inhabits closed canopy evergreen forests, although these birds are also reported to use areas that have been selectively logged (2).

Little information on the natural ecology and behaviour of this rare forest bird is known, due to a lack of sightings and research. It is thought that breeding occurs in March on the island of Panay, and eggs and chicks are reportedly collected between May and July (5). Clutch size is estimated at between two and three eggs and nests have been recorded in Shorea polysperma trees, known locally as 'balakbakan' (5), or in disused woodpecker holes (2). Hornbills have an unusual nesting strategy where the female seals herself inside the tree cavity and relies on the male to bring food to her and the developing young throughout her imprisonment; in the case of the wrinkled hornbill this lasts until the chicks are fully fledged (7).

From the few records that exist, the major food component appears to be fruit; birds have been observed feeding on figs, and a flock of 25 to 30 birds were seen to feed in Aglaia trees when they were bearing fruit (5).

Habitat loss in the form of deforestation has been the major cause of the precipitous decline in the Visayan wrinkled hornbill and has resulted in its local extinction from the island of Guimaras (4). Shifting agriculture has cleared vast areas of forest, and development and plantations have also played a part in habitat loss (6). In 1988, it was estimated that only four percent of Negros and eight percent of Panay remained forested (4). These birds have also been hunted for food and for collection for the pet trade in parts of their range, and the isolated, fragments of populations that remain are extremely vulnerable to any chance event such as the local failure of fruiting trees (4).

This species appears to be on the brink of extinction unless concerted efforts are made. It is currently listed on Appendix II of the Convention on International Trade in Endangered Species (CITES) and has been the target of conservation efforts of a number of well-known conservation organisations such as Frankfurt Zoo (PESCP), ZGAP and Flora and Fauna International (FFI) (5). In April 2002, the northwest peninsular of Panay was declared a National Park and has been recognised as an Important Bird Area (IBA) (6).

For more information on the Visayan wrinkled hornbill see:

• BirdLife International's World Bird Database:
  www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=966&m=0
• BirdLife International. (2001) Threatened Birds of Asia: the BirdLife International Red Data Book. BirdLife International, Cambridge, UK.
• BirdLife International. (2000) Threatened Birds of the World. Lynx Edicions and BirdLife International, Barcelona and Cambridge.

Authenticated by BirdLife International Secretariat.
http://www.birdlife.org